The proposed program of research is concerned with how language users take into account the common ground shared with others. A theoretical position is described that views common ground as an emergent property of how people encode and retrieve information with respect to others. On this account, a routine consequence of interaction is the creation of associations in memory which enable other individuals to serve as cues to make associated information more readily accessible. Thus, effects attributable to common ground can be understood as being motivated by the same domain-general cognitive psychological mechanisms that contribute to other related phenomena, like source memory. Four experiments are proposed that explore whether partner-specific memory associations can influence aspects of language production that are not overtly communicative. Each experiment consists of three phases: 1) an initial category exemplar generation task in which participants are given the opportunity to associate generated items with each of two experimental partners, 2) a language production task carried out in the presence of the same two partners, and 3) a final source memory test which assesses the degree of partner-specific encoding. Experiments 1 and 2 test whether the presence of the same experimental partner speeds naming responses in a picture naming task. Experiments 3 and 4 build upon known accessibility effects in language production and examine the effect of partner on order of mention in a picture description task. Importantly, the generality of the proposed account of common ground is tested by examining these effects in both younger and older adults. Prior research has shown that older adults have difficulties encoding associations between task material and context. If so, they may be less likely to demonstrate sensitivity to specific partners during social interaction. The goals of this project are to motivate a more fully-specified model of the cognitive mechanisms that mediate the ability of language users to take into account common ground. [unreadable] [unreadable]